Abstract: A methane separation method of the present invention at least includes: mixing the biogas and an absorbing liquid that absorbs carbon dioxide in a mixer so as to form a mixed fluid of a gas-liquid mixed phase; introducing the mixed fluid into a first gas/liquid separator so as to separate the mixed fluid through gas/liquid separation into methane and a CO2-absorbed liquid formed due to an absorption of the carbon dioxide by the absorbing liquid; recovering methane separated in the first gas/liquid separator; and supplying the CO2-absorbed liquid through a supply port of a membrane module comprised of a container and a plurality of hollow fiber permeable membranes built therein to inside of the membranes so as to make the CO2-absorbed liquid permeate the permeable membranes, and lowering a pressure outside the permeable membranes to a level lower than that inside the permeable membranes.

Abstract: A methane separation method of the present invention at least includes: mixing the biogas and an absorbing liquid that absorbs carbon dioxide in a mixer so as to form a mixed fluid of a gas-liquid mixed phase; introducing the mixed fluid into a first gas/liquid separator so as to separate the mixed fluid through gas/liquid separation into methane and a CO2-absorbed liquid formed due to an absorption of the carbon dioxide by the absorbing liquid; recovering methane separated in the first gas/liquid separator; and supplying the CO2-absorbed liquid through a supply port of a membrane module comprised of a container and a plurality of hollow fiber permeable membranes built therein to inside of the membranes so as to make the CO2-absorbed liquid permeate the permeable membranes, and lowering a pressure outside the permeable membranes to a level lower than that inside the permeable membranes.

Abstract: In an apparatus for clock tree synthesis allocation wiring, the wiring is appropriately conducting while minimizing the wiring cost and power consumed in operation. A first file stores therein information of operating frequencies of clock lines. Second file stores therein information of a maximum capacity allowed for a clock buffer for each operating frequency obtained according to restriction of electro-migration. A maximum capacity determining device determines a maximum capacity allowed for an operating frequency according to information of the operating frequency from the input device, information of the operating frequencies stored in the first file, and information of the maximum capacity stored in the second file. A tool for clock tree synthesis allocation wiring conducts wiring by assuming the maximum capacity to be a limiting value of a maximum capacity which can be added to each clock buffer.

Abstract: A process for fabricating a semiconductor device comprising the steps of forming a gate insulation layer on a first conductive type semiconductor substrate, forming a polycrystalline silicon layer on the gate insulation layer, and selectively removing the polycrystalline silicon layer to form a gate electrode and a direct contact electrode. The process also includes a step of forming a photoresist mask masking the direct contact electrode at least at the side opposing the gate electrode, and performing ion implantation of a second conductive type impurity for forming an impurity diffused layer at both sides of the gate electrode. The direct contact electrode and the impurity diffused layer are electrically connected by a conductive layer covering the surface of one of the impurity diffused layer and the side surface of the direct contact electrode.

Abstract: A membrane for the separation of carbon dioxide is disclosed which includes a hydrogel film of a cross-linked, vinyl alcohol/acrylic acid salt copolymer impregnated with an aqueous carrier solution containing a carbon dioxide carrier dissolved therein. A composition containing a solvent, an alkali metal carbonate or bicarbonates, and a polydentate ligand capable of forming a complex with an alkali metal ion is suitably used as the carrier solution. This composition may also be used for the preparation of a liquid film of a carbon dioxide separation membrane.

Abstract: Disclosed is an improved metal oxide-semiconductor field-effect transistor having two diffused regions extending apart from under one and the other edge of the gate in the opposite directions, at least one of the diffused regions being composed of a first leastdoped, short section, a second lightly-doped, short section, and a third heavily-doped, long section. Either diffused region may be used as drain. The series-connection of least and lightly-doped sections of the same longitudinal size or depth improves the current driving capability of the semiconductor device. Also, methods of making such MOSFETs are disclosed.

Abstract: A tubular prosthesis having a composite structure comprising (i) tubular polytetrafluoroethylene having a microfibrous structure comprising small nodes interconnected with fibrils and (ii) materials which can be absorbed by a living body wherein (a) said polytetrafluoroethylene has a greater average fibril length on the outer surface than on the inner surface, and the fibrous structure of said polytetrafluoroethylene varies continuously across the thickness of the tube wall wherein said inner surface has said fibrous structure being predominantly oriented along the axial direction and said outer surface has said fibrous structure being predominantly oriented along the concentric direction; and (b) said materials which can be absorbed by a living body are collagen, at least one of albumin and chitosan, and heparin, and are distributed in such a manner that collagen is present in the portion of the tube wall which is closest to the outer surface thereof while at least one of albumin and chitosan is present in t